CVE-2022-49450
In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix listen() setting the bar too high for the prealloc rings AF_RXRPC's listen() handler lets you set the backlog up to 32 (if you bump up the sysctl), but whilst the…
Does this matter?
Lower severity and a low EPSS score (0.29%). Track it; it rarely justifies an emergency change on its own.
Description
In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix listen() setting the bar too high for the prealloc rings AF_RXRPC's listen() handler lets you set the backlog up to 32 (if you bump up the sysctl), but whilst the preallocation circular buffers have 32 slots in them, one of them has to be a dead slot because we're using CIRC_CNT(). This means that listen(rxrpc_sock, 32) will cause an oops when the socket is closed because rxrpc_service_prealloc_one() allocated one too many calls and rxrpc_discard_prealloc() won't then be able to get rid of them because it'll think the ring is empty. rxrpc_release_calls_on_socket() then tries to abort them, but oopses because call->peer isn't yet set. Fix this by setting the maximum backlog to RXRPC_BACKLOG_MAX - 1 to match the ring capacity. BUG: kernel NULL pointer dereference, address: 0000000000000086 ... RIP: 0010:rxrpc_send_abort_packet+0x73/0x240 [rxrpc] Call Trace: <TASK> ? __wake_up_common_lock+0x7a/0x90 ? rxrpc_notify_socket+0x8e/0x140 [rxrpc] ? rxrpc_abort_call+0x4c/0x60 [rxrpc] rxrpc_release_calls_on_socket+0x107/0x1a0 [rxrpc] rxrpc_release+0xc9/0x1c0 [rxrpc] __sock_release+0x37/0xa0 sock_close+0x11/0x20 __fput+0x89/0x240 task_work_run+0x59/0x90 do_exit+0x319/0xaa0
- CVSS 3.1
- 5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.29% probability · 22th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-476
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/369de57492c4f1a42563c5a3bd365822ca3bfc79Patch
- https://git.kernel.org/stable/c/4a3a78b7918bdd723d8c7c9786522ca969bffcc4Patch
- https://git.kernel.org/stable/c/5b4826657d36c218e9f08e8d3223b0edce3de88fPatch
- https://git.kernel.org/stable/c/616f76498d5ddf26b997caf64a95cda3c8a55533Patch
- https://git.kernel.org/stable/c/61fb38cfbb1d54d3dafd0c25752f684b3cd00b32Patch
- https://git.kernel.org/stable/c/88e22159750b0d55793302eeed8ee603f5c1a95cPatch
- https://git.kernel.org/stable/c/91b34bf0409f43bb60453bab23c5beadd726d022Patch
- https://git.kernel.org/stable/c/b3a9b227d5e7467b8518160ff034ea22bb9de573Patch
- https://git.kernel.org/stable/c/e198f1930050e3115c80b67d9249f80f98a27c67Patch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.